Network Security and Cryptography
5 June 2024
Examination Paper
Answer ALL questions.
Clearly cross out surplus answers.
Time: 3 hours
The maximum mark for this paper is 100.
Any reference material brought into the examination room must be
handed to the invigilator before the start of the examination
Marks
Answer ALL questions
Marks
Question 1
a) Describe FOUR (4) criteria that are necessary for an encryption scheme to be 4
considered computationally secure.
b) Explain what is meant by a cryptographic hash function and list FOUR (4) 6
common examples of cryptographic hash functions.
Total 10 Marks
Question 2
a) Explain the difference between symmetric and asymmetric encryption. Your 6
answer should include ONE (1) diagram for symmetric encryption and ONE (1)
diagram for asymmetric encryption. Your annotated diagrams should clearly
show:
• The components involved in each type of encryption.
• How the keys are used in each algorithm
• The flow of information during encryption and decryption
b) Explain what is meant by a digital certificate and explain TWO (2) common 4
methods that can be used to generate digital certificates.
Total 10 Marks
Question 3
a) Explain what IPSec is and describe TWO (2) applications of IPSec. 4
b) Describe TWO (2) major differences between HTTP and HTTPS and explain 6
how a browser shows which protocol is being used.
Total 10 Marks
Question 4
a) Describe THREE (3) uses of cryptography in email communication. 6
b) Describe TWO (2) potential drawbacks or challenges of implementing secure 4
email for an organisation.
Total 10 Marks
Questions continue on the next page
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Network Security and Cryptography © NCC Education Limited 2024
Marks
Question 5
a) Describe THREE (3) examples of sensitive organisational data that hackers would 6
find valuable to obtain.
b) List FOUR (4) methods that can be used to protect an organisation's data in the 4
case of a hacker successfully gaining access.
Total 10 Marks
Question 6
a) Explain what is meant by a security vulnerability and describe TWO (2) potential 6
effects that vulnerabilities can have on systems and networks.
b) Describe TWO (2) ways in which vulnerabilities can be introduced into an 4
organisation’s IT systems and networks.
Total 10 Marks
Question 7
a) Describe TWO (2) methods that an organisation can use to identify existing 4
security vulnerabilities in its network.
b) Describe THREE (3) methods that a hacker can use to obtain or crack a weak 6
password.
Total 10 Marks
Question 8
a) Describe the TWO (2) core steps involved in authenticating a user accessing a 4
network.
b) Explain what is meant by biometric authentication and list FOUR (4) examples of 6
biometric authentication methods.
Total 10 Marks
Questions continue on the next page
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Network Security and Cryptography © NCC Education Limited 2024
Marks
Question 9
a) Describe the THREE (3) main steps to correctly configuring static packet filters. 6
b) Explain the concept of Network Address Translation (NAT). 2
c) Describe the difference between hardware and software firewalls. 2
Total 10 Marks
Question 10
a) Explain what is meant by a Virtual Private Network (VPN) and describe TWO (2) 6
main types of SSL VPN.
b) Describe the main flaws with Wired Equivalent Privacy (WEP) used in wireless 4
networks.
Total 10 Marks
End of Paper
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Network Security and Cryptography © NCC Education Limited 2024
